After unwrapping your mount, squeeze the tabs circled in yellow to open the tilting mechanism.
Mounting:
While holding alignment between the front of the slider and desk, secure the slider to the desk using the 4 supplied screws through the integrated holes.
Insert the bottom edge of the Stream Deck into the mount so the bottom edges are flush
Finally, press the top corners of the Stream Deck into the mount
Feed the USB cable through the cable management loop and plug into rear of Stream Deck. This step may vary depending on the dock you are using.